The broad long-term goal of this research program is to produce an educational program to train certified tumor registrars (CTR) also referred to as cancer registrars to code comorbidity information for inclusion into cancer registries. Because of the demonstrated importance of comorbidity in cancer statistics, inclusion of this information will improve the accuracy of survival statistics and the evaluation of treatment effectiveness. Improved accuracy of cancer statistics and evaluation of treatment effectiveness will decrease mortality and improve quality of life for cancer patients. This research is important because if cancer registrars code comorbidity accurately, consistently, and efficiently, then comorbidity information can be included into standard oncology data collection efforts. The specific aims of this continuation project are: 1. To demonstrate that the teaching program created during previous research (R25 CA68304) has broad generalizability to certified tumor registrars at a variety of different oncology data centers across the United States (ie., small, rural, community and large, urban centers) 2. To work with the American College of Surgeons' Commission on Cancer and the National Cancer Registrars Association to advocate for the inclusion of comorbidity information in national cancer databases. This project will be a two-year, prospective, longitudinal study with two distinct phases. Phase One will include the education and assessment of certified tumor registrars coding comorbidity at 5 distinct oncology data centers across the United States. The CTRs will receive the teaching program created during the previous research. Assessment of the teaching program will include quantitative measures of accuracy, validity, and reliability. In Phase Two, the investigators will work with the national cancer agencies listed above to include comorbidity information in national cancer data bases. It is anticipated that several meetings with representatives of each group will be required. During these meetings the investigators will demonstrate the importance of comorbidity, the educational program, and the results of the validity assessment. The PI will work with these representatives to follow the proper procedures for inclusion of comorbidity as a new data element into national cancer databases. The intended outcome of this project is the demonstration of the validity and generalizability of the educational program created at Barnes-Jewish Hospital to train Certified Tumor Registrars to code comorbidity. Once it has been demonstrated that comorbidity can be coded accurately and reliably, the investigators plan to work with national cancer organizations to include comorbidity in standard oncology databases.